The frames of hand trucks are normally of open or skeleton frame work configuration and include side rail channels in opposing disposition to receive cross brace or cross rail members, which are spaced apart vertically along the frame. The two-wheeled variety of hand truck includes a primary frame adapted in use to assume a generally vertically inclined position. The primary frame includes a generally forwardly projecting cargo supporting nose and at its upper end incorporates a handle portion which is graspable by a user to propel the truck along a path, or up or down a stairway, for example. While hand trucks for transporting cylindrical products such as barrels normally include curvilinear cross rails, two wheeled hand trucks with linear cross rails are also frequently pressed into service to transport heavy barrels, despite the fact there is a substantially line contact of the barrel with the cross rails. Thus, dependent on the “use of the day”, the cross rails are expected to bear a considerable load which may be centrally applied at a relatively limited load contact location, or which may be spread over a substantial portion of the length of the cross rail and the side rails. Not only are the cross rails and side rails therefore subject to considerable shear stresses, however, they also are subjected to severe torsional stresses. Such stresses are applied when one wheel of the hand truck is up on a curb and the other is moving to the pavement below or when a load is dumped sidewise off the hand truck, for example.
In the present assignee's Mortenson patent, U.S. Pat. No. 4,563,014, which I incorporate herein by reference, curvilinear injection molded cross braces are utilized, which have vertically aligned sockets for telescopically receiving the ends of the handle and for receiving lightweight package bracing tubes. The ends of the plastic cross rails are received within the side rail channels, but the fastening system requires specially formed brace end walls for receiving a screw, washer and nut assembly. The side rail configuration is not configured as to secure to an inturned portion of the wheel supporting brackets, in addition to the front ends of the brackets.